gecko-dev/accessible/mac/GeckoTextMarker.mm

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/* clang-format off */
/* -*- Mode: Objective-C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* clang-format on */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "DocAccessibleParent.h"
#include "AccAttributes.h"
#include "nsCocoaUtils.h"
#include "mozilla/a11y/DocAccessiblePlatformExtParent.h"
#import "GeckoTextMarker.h"
extern "C" {
CFTypeID AXTextMarkerGetTypeID();
AXTextMarkerRef AXTextMarkerCreate(CFAllocatorRef allocator, const UInt8* bytes,
CFIndex length);
const UInt8* AXTextMarkerGetBytePtr(AXTextMarkerRef text_marker);
size_t AXTextMarkerGetLength(AXTextMarkerRef text_marker);
CFTypeID AXTextMarkerRangeGetTypeID();
AXTextMarkerRangeRef AXTextMarkerRangeCreate(CFAllocatorRef allocator,
AXTextMarkerRef start_marker,
AXTextMarkerRef end_marker);
AXTextMarkerRef AXTextMarkerRangeCopyStartMarker(
AXTextMarkerRangeRef text_marker_range);
AXTextMarkerRef AXTextMarkerRangeCopyEndMarker(
AXTextMarkerRangeRef text_marker_range);
}
namespace mozilla {
namespace a11y {
struct OpaqueGeckoTextMarker {
OpaqueGeckoTextMarker(uintptr_t aDoc, uintptr_t aID, int32_t aOffset)
: mDoc(aDoc), mID(aID), mOffset(aOffset) {}
OpaqueGeckoTextMarker() {}
uintptr_t mDoc;
uintptr_t mID;
int32_t mOffset;
};
static bool DocumentExists(Accessible* aDoc, uintptr_t aDocPtr) {
if (reinterpret_cast<uintptr_t>(aDoc) == aDocPtr) {
return true;
}
if (aDoc->IsLocal()) {
DocAccessible* docAcc = aDoc->AsLocal()->AsDoc();
uint32_t docCount = docAcc->ChildDocumentCount();
for (uint32_t i = 0; i < docCount; i++) {
if (DocumentExists(docAcc->GetChildDocumentAt(i), aDocPtr)) {
return true;
}
}
} else {
DocAccessibleParent* docProxy = aDoc->AsRemote()->AsDoc();
size_t docCount = docProxy->ChildDocCount();
for (uint32_t i = 0; i < docCount; i++) {
if (DocumentExists(docProxy->ChildDocAt(i), aDocPtr)) {
return true;
}
}
}
return false;
}
// GeckoTextMarker
GeckoTextMarker::GeckoTextMarker(Accessible* aDoc,
AXTextMarkerRef aTextMarker) {
MOZ_ASSERT(aDoc);
OpaqueGeckoTextMarker opaqueMarker;
if (aTextMarker &&
AXTextMarkerGetLength(aTextMarker) == sizeof(OpaqueGeckoTextMarker)) {
memcpy(&opaqueMarker, AXTextMarkerGetBytePtr(aTextMarker),
sizeof(OpaqueGeckoTextMarker));
if (DocumentExists(aDoc, opaqueMarker.mDoc)) {
Accessible* doc = reinterpret_cast<Accessible*>(opaqueMarker.mDoc);
if (doc->IsRemote()) {
mContainer = doc->AsRemote()->AsDoc()->GetAccessible(opaqueMarker.mID);
} else {
mContainer = doc->AsLocal()->AsDoc()->GetAccessibleByUniqueID(
reinterpret_cast<void*>(opaqueMarker.mID));
}
}
mOffset = opaqueMarker.mOffset;
} else {
mContainer = nullptr;
mOffset = 0;
}
}
GeckoTextMarker GeckoTextMarker::MarkerFromIndex(Accessible* aRoot,
int32_t aIndex) {
if (aRoot->IsRemote()) {
int32_t offset = 0;
uint64_t containerID = 0;
DocAccessibleParent* ipcDoc = aRoot->AsRemote()->Document();
Unused << ipcDoc->GetPlatformExtension()->SendOffsetAtIndex(
aRoot->AsRemote()->ID(), aIndex, &containerID, &offset);
RemoteAccessible* container = ipcDoc->GetAccessible(containerID);
return GeckoTextMarker(container, offset);
} else if (auto htWrap = static_cast<HyperTextAccessibleWrap*>(
aRoot->AsLocal()->AsHyperText())) {
int32_t offset = 0;
HyperTextAccessible* container = nullptr;
htWrap->OffsetAtIndex(aIndex, &container, &offset);
return GeckoTextMarker(container, offset);
}
return GeckoTextMarker();
}
id GeckoTextMarker::CreateAXTextMarker() {
if (!IsValid()) {
return nil;
}
Accessible* doc;
if (mContainer->IsRemote()) {
doc = mContainer->AsRemote()->Document();
} else {
doc = mContainer->AsLocal()->Document();
}
uintptr_t identifier =
mContainer->IsRemote()
? mContainer->AsRemote()->ID()
: reinterpret_cast<uintptr_t>(mContainer->AsLocal()->UniqueID());
OpaqueGeckoTextMarker opaqueMarker(reinterpret_cast<uintptr_t>(doc),
identifier, mOffset);
AXTextMarkerRef cf_text_marker = AXTextMarkerCreate(
kCFAllocatorDefault, reinterpret_cast<const UInt8*>(&opaqueMarker),
sizeof(OpaqueGeckoTextMarker));
return [static_cast<id>(cf_text_marker) autorelease];
}
bool GeckoTextMarker::operator<(const GeckoTextMarker& aPoint) const {
if (mContainer == aPoint.mContainer) return mOffset < aPoint.mOffset;
// Build the chain of parents
AutoTArray<Accessible*, 30> parents1, parents2;
Accessible* p1 = mContainer;
while (p1) {
parents1.AppendElement(p1);
p1 = p1->Parent();
}
Accessible* p2 = aPoint.mContainer;
while (p2) {
parents2.AppendElement(p2);
p2 = p2->Parent();
}
// An empty chain of parents means one of the containers was null.
MOZ_ASSERT(parents1.Length() != 0 && parents2.Length() != 0,
"have empty chain of parents!");
// Find where the parent chain differs
uint32_t pos1 = parents1.Length(), pos2 = parents2.Length();
for (uint32_t len = std::min(pos1, pos2); len > 0; --len) {
Accessible* child1 = parents1.ElementAt(--pos1);
Accessible* child2 = parents2.ElementAt(--pos2);
if (child1 != child2) {
return child1->IndexInParent() < child2->IndexInParent();
}
}
if (pos1 != 0) {
// If parents1 is a superset of parents2 then mContainer is a
// descendant of aPoint.mContainer. The next element down in parents1
// is mContainer's ancestor that is the child of aPoint.mContainer.
// We compare its end offset in aPoint.mContainer with aPoint.mOffset.
Accessible* child = parents1.ElementAt(pos1 - 1);
MOZ_ASSERT(child->Parent() == aPoint.mContainer);
bool unused;
uint32_t endOffset = child->IsRemote()
? child->AsRemote()->EndOffset(&unused)
: child->AsLocal()->EndOffset();
return endOffset < static_cast<uint32_t>(aPoint.mOffset);
}
if (pos2 != 0) {
// If parents2 is a superset of parents1 then aPoint.mContainer is a
// descendant of mContainer. The next element down in parents2
// is aPoint.mContainer's ancestor that is the child of mContainer.
// We compare its start offset in mContainer with mOffset.
Accessible* child = parents2.ElementAt(pos2 - 1);
MOZ_ASSERT(child->Parent() == mContainer);
bool unused;
uint32_t startOffset = child->IsRemote()
? child->AsRemote()->StartOffset(&unused)
: child->AsLocal()->StartOffset();
return static_cast<uint32_t>(mOffset) <= startOffset;
}
MOZ_ASSERT_UNREACHABLE("Broken tree?!");
return false;
}
bool GeckoTextMarker::IsEditableRoot() {
uint64_t state = mContainer->IsRemote() ? mContainer->AsRemote()->State()
: mContainer->AsLocal()->State();
if ((state & states::EDITABLE) == 0) {
return false;
}
Accessible* parent = mContainer->Parent();
if (!parent) {
// Not sure when this can happen, but it would technically be an editable
// root.
return true;
}
state = parent->IsRemote() ? parent->AsRemote()->State()
: parent->AsLocal()->State();
return (state & states::EDITABLE) == 0;
}
bool GeckoTextMarker::Next() {
if (mContainer->IsRemote()) {
int32_t nextOffset = 0;
uint64_t nextContainerID = 0;
DocAccessibleParent* ipcDoc = mContainer->AsRemote()->Document();
Unused << ipcDoc->GetPlatformExtension()->SendNextClusterAt(
mContainer->AsRemote()->ID(), mOffset, &nextContainerID, &nextOffset);
RemoteAccessible* nextContainer = ipcDoc->GetAccessible(nextContainerID);
bool moved =
nextContainer != mContainer->AsRemote() || nextOffset != mOffset;
mContainer = nextContainer;
mOffset = nextOffset;
return moved;
} else if (auto htWrap = ContainerAsHyperTextWrap()) {
HyperTextAccessible* nextContainer = nullptr;
int32_t nextOffset = 0;
htWrap->NextClusterAt(mOffset, &nextContainer, &nextOffset);
bool moved = nextContainer != htWrap || nextOffset != mOffset;
mContainer = nextContainer;
mOffset = nextOffset;
return moved;
}
return false;
}
bool GeckoTextMarker::Previous() {
if (mContainer->IsRemote()) {
int32_t prevOffset = 0;
uint64_t prevContainerID = 0;
DocAccessibleParent* ipcDoc = mContainer->AsRemote()->Document();
Unused << ipcDoc->GetPlatformExtension()->SendPreviousClusterAt(
mContainer->AsRemote()->ID(), mOffset, &prevContainerID, &prevOffset);
RemoteAccessible* prevContainer = ipcDoc->GetAccessible(prevContainerID);
bool moved =
prevContainer != mContainer->AsRemote() || prevOffset != mOffset;
mContainer = prevContainer;
mOffset = prevOffset;
return moved;
} else if (auto htWrap = ContainerAsHyperTextWrap()) {
HyperTextAccessible* prevContainer = nullptr;
int32_t prevOffset = 0;
htWrap->PreviousClusterAt(mOffset, &prevContainer, &prevOffset);
bool moved = prevContainer != htWrap || prevOffset != mOffset;
mContainer = prevContainer;
mOffset = prevOffset;
return moved;
}
return false;
}
static uint32_t CharacterCount(Accessible* aContainer) {
if (aContainer->IsRemote()) {
return aContainer->AsRemote()->CharacterCount();
}
if (aContainer->AsLocal()->IsHyperText()) {
return aContainer->AsLocal()->AsHyperText()->CharacterCount();
}
return 0;
}
GeckoTextMarkerRange GeckoTextMarker::Range(EWhichRange aRangeType) {
MOZ_ASSERT(mContainer);
if (mContainer->IsRemote()) {
int32_t startOffset = 0, endOffset = 0;
uint64_t startContainerID = 0, endContainerID = 0;
DocAccessibleParent* ipcDoc = mContainer->AsRemote()->Document();
bool success = ipcDoc->GetPlatformExtension()->SendRangeAt(
mContainer->AsRemote()->ID(), mOffset, aRangeType, &startContainerID,
&startOffset, &endContainerID, &endOffset);
if (success) {
return GeckoTextMarkerRange(
GeckoTextMarker(ipcDoc->GetAccessible(startContainerID), startOffset),
GeckoTextMarker(ipcDoc->GetAccessible(endContainerID), endOffset));
}
} else if (auto htWrap = ContainerAsHyperTextWrap()) {
int32_t startOffset = 0, endOffset = 0;
HyperTextAccessible* startContainer = nullptr;
HyperTextAccessible* endContainer = nullptr;
htWrap->RangeAt(mOffset, aRangeType, &startContainer, &startOffset,
&endContainer, &endOffset);
return GeckoTextMarkerRange(GeckoTextMarker(startContainer, startOffset),
GeckoTextMarker(endContainer, endOffset));
}
return GeckoTextMarkerRange(GeckoTextMarker(), GeckoTextMarker());
}
Accessible* GeckoTextMarker::Leaf() {
MOZ_ASSERT(mContainer);
if (mContainer->IsRemote()) {
uint64_t leafID = 0;
DocAccessibleParent* ipcDoc = mContainer->AsRemote()->Document();
Unused << ipcDoc->GetPlatformExtension()->SendLeafAtOffset(
mContainer->AsRemote()->ID(), mOffset, &leafID);
return ipcDoc->GetAccessible(leafID);
} else if (auto htWrap = ContainerAsHyperTextWrap()) {
return htWrap->LeafAtOffset(mOffset);
}
return mContainer;
}
// GeckoTextMarkerRange
GeckoTextMarkerRange::GeckoTextMarkerRange(
Accessible* aDoc, AXTextMarkerRangeRef aTextMarkerRange) {
if (!aTextMarkerRange ||
CFGetTypeID(aTextMarkerRange) != AXTextMarkerRangeGetTypeID()) {
return;
}
AXTextMarkerRef start_marker(
AXTextMarkerRangeCopyStartMarker(aTextMarkerRange));
AXTextMarkerRef end_marker(AXTextMarkerRangeCopyEndMarker(aTextMarkerRange));
mStart = GeckoTextMarker(aDoc, start_marker);
mEnd = GeckoTextMarker(aDoc, end_marker);
CFRelease(start_marker);
CFRelease(end_marker);
}
GeckoTextMarkerRange::GeckoTextMarkerRange(Accessible* aAccessible) {
if (aAccessible->IsHyperText()) {
// The accessible is a hypertext. Initialize range to its inner text range.
mStart = GeckoTextMarker(aAccessible, 0);
mEnd = GeckoTextMarker(aAccessible, (CharacterCount(aAccessible)));
} else {
// The accessible is not a hypertext (maybe a text leaf?). Initialize range
// to its offsets in its container.
mStart = GeckoTextMarker(aAccessible->Parent(), 0);
mEnd = GeckoTextMarker(aAccessible->Parent(), 0);
if (mStart.mContainer->IsRemote()) {
DocAccessibleParent* ipcDoc = mStart.mContainer->AsRemote()->Document();
Unused << ipcDoc->GetPlatformExtension()->SendRangeOfChild(
mStart.mContainer->AsRemote()->ID(), aAccessible->AsRemote()->ID(),
&mStart.mOffset, &mEnd.mOffset);
} else if (auto htWrap = mStart.ContainerAsHyperTextWrap()) {
htWrap->RangeOfChild(aAccessible->AsLocal(), &mStart.mOffset,
&mEnd.mOffset);
}
}
}
id GeckoTextMarkerRange::CreateAXTextMarkerRange() {
if (!IsValid()) {
return nil;
}
AXTextMarkerRangeRef cf_text_marker_range =
AXTextMarkerRangeCreate(kCFAllocatorDefault, mStart.CreateAXTextMarker(),
mEnd.CreateAXTextMarker());
return [static_cast<id>(cf_text_marker_range) autorelease];
}
NSString* GeckoTextMarkerRange::Text() const {
nsAutoString text;
if (mStart.mContainer->IsRemote() && mEnd.mContainer->IsRemote()) {
DocAccessibleParent* ipcDoc = mStart.mContainer->AsRemote()->Document();
Unused << ipcDoc->GetPlatformExtension()->SendTextForRange(
mStart.mContainer->AsRemote()->ID(), mStart.mOffset,
mEnd.mContainer->AsRemote()->ID(), mEnd.mOffset, &text);
} else if (auto htWrap = mStart.ContainerAsHyperTextWrap()) {
htWrap->TextForRange(text, mStart.mOffset, mEnd.ContainerAsHyperTextWrap(),
mEnd.mOffset);
}
return nsCocoaUtils::ToNSString(text);
}
static NSColor* ColorFromColor(const Color& aColor) {
return [NSColor colorWithCalibratedRed:NS_GET_R(aColor.mValue) / 255.0
green:NS_GET_G(aColor.mValue) / 255.0
blue:NS_GET_B(aColor.mValue) / 255.0
alpha:1.0];
}
static NSDictionary* StringAttributesFromAttributes(AccAttributes* aAttributes,
Accessible* aContainer) {
NSMutableDictionary* attrDict =
[NSMutableDictionary dictionaryWithCapacity:aAttributes->Count()];
NSMutableDictionary* fontAttrDict = [[NSMutableDictionary alloc] init];
[attrDict setObject:fontAttrDict forKey:@"AXFont"];
for (auto iter : *aAttributes) {
if (iter.Name() == nsGkAtoms::backgroundColor) {
if (Maybe<Color> value = iter.Value<Color>()) {
NSColor* color = ColorFromColor(*value);
[attrDict setObject:(__bridge id)color.CGColor
forKey:@"AXBackgroundColor"];
}
} else if (iter.Name() == nsGkAtoms::color) {
if (Maybe<Color> value = iter.Value<Color>()) {
NSColor* color = ColorFromColor(*value);
[attrDict setObject:(__bridge id)color.CGColor
forKey:@"AXForegroundColor"];
}
} else if (iter.Name() == nsGkAtoms::font_size) {
if (Maybe<FontSize> pointSize = iter.Value<FontSize>()) {
int32_t fontPixelSize = static_cast<int32_t>(pointSize->mValue * 4 / 3);
[fontAttrDict setObject:@(fontPixelSize) forKey:@"AXFontSize"];
}
} else if (iter.Name() == nsGkAtoms::font_family) {
nsAutoString fontFamily;
iter.ValueAsString(fontFamily);
[fontAttrDict setObject:nsCocoaUtils::ToNSString(fontFamily)
forKey:@"AXFontFamily"];
} else if (iter.Name() == nsGkAtoms::textUnderlineColor) {
[attrDict setObject:@1 forKey:@"AXUnderline"];
if (Maybe<Color> value = iter.Value<Color>()) {
NSColor* color = ColorFromColor(*value);
[attrDict setObject:(__bridge id)color.CGColor
forKey:@"AXUnderlineColor"];
}
} else if (iter.Name() == nsGkAtoms::invalid) {
// XXX: There is currently no attribute for grammar
if (auto value = iter.Value<RefPtr<nsAtom>>()) {
if (*value == nsGkAtoms::spelling) {
[attrDict setObject:@YES
forKey:NSAccessibilityMarkedMisspelledTextAttribute];
}
}
} else {
nsAutoString valueStr;
iter.ValueAsString(valueStr);
nsAutoString keyStr;
iter.NameAsString(keyStr);
[attrDict setObject:nsCocoaUtils::ToNSString(valueStr)
forKey:nsCocoaUtils::ToNSString(keyStr)];
}
}
mozAccessible* container = GetNativeFromGeckoAccessible(aContainer);
id<MOXAccessible> link =
[container moxFindAncestor:^BOOL(id<MOXAccessible> moxAcc, BOOL* stop) {
return [[moxAcc moxRole] isEqualToString:NSAccessibilityLinkRole];
}];
if (link) {
[attrDict setObject:link forKey:@"AXLink"];
}
id<MOXAccessible> heading =
[container moxFindAncestor:^BOOL(id<MOXAccessible> moxAcc, BOOL* stop) {
return [[moxAcc moxRole] isEqualToString:@"AXHeading"];
}];
if (heading) {
[attrDict setObject:[heading moxValue] forKey:@"AXHeadingLevel"];
}
return attrDict;
}
NSAttributedString* GeckoTextMarkerRange::AttributedText() const {
NSMutableAttributedString* str =
[[[NSMutableAttributedString alloc] init] autorelease];
if (mStart.mContainer->IsRemote() && mEnd.mContainer->IsRemote()) {
nsTArray<TextAttributesRun> textAttributesRuns;
DocAccessibleParent* ipcDoc = mStart.mContainer->AsRemote()->Document();
Unused << ipcDoc->GetPlatformExtension()->SendAttributedTextForRange(
mStart.mContainer->AsRemote()->ID(), mStart.mOffset,
mEnd.mContainer->AsRemote()->ID(), mEnd.mOffset, &textAttributesRuns);
for (size_t i = 0; i < textAttributesRuns.Length(); i++) {
AccAttributes* attributes =
textAttributesRuns.ElementAt(i).TextAttributes();
RemoteAccessible* container =
ipcDoc->GetAccessible(textAttributesRuns.ElementAt(i).ContainerID());
NSAttributedString* substr = [[[NSAttributedString alloc]
initWithString:nsCocoaUtils::ToNSString(
textAttributesRuns.ElementAt(i).Text())
attributes:StringAttributesFromAttributes(attributes, container)]
autorelease];
[str appendAttributedString:substr];
}
} else if (auto htWrap = mStart.ContainerAsHyperTextWrap()) {
nsTArray<nsString> texts;
nsTArray<LocalAccessible*> containers;
nsTArray<RefPtr<AccAttributes>> props;
htWrap->AttributedTextForRange(texts, props, containers, mStart.mOffset,
mEnd.ContainerAsHyperTextWrap(),
mEnd.mOffset);
MOZ_ASSERT(texts.Length() == props.Length() &&
texts.Length() == containers.Length());
for (size_t i = 0; i < texts.Length(); i++) {
NSAttributedString* substr = [[[NSAttributedString alloc]
initWithString:nsCocoaUtils::ToNSString(texts.ElementAt(i))
attributes:StringAttributesFromAttributes(
props.ElementAt(i), containers.ElementAt(i))]
autorelease];
[str appendAttributedString:substr];
}
}
return str;
}
int32_t GeckoTextMarkerRange::Length() const {
int32_t length = 0;
if (mStart.mContainer->IsRemote() && mEnd.mContainer->IsRemote()) {
DocAccessibleParent* ipcDoc = mStart.mContainer->AsRemote()->Document();
Unused << ipcDoc->GetPlatformExtension()->SendLengthForRange(
mStart.mContainer->AsRemote()->ID(), mStart.mOffset,
mEnd.mContainer->AsRemote()->ID(), mEnd.mOffset, &length);
} else if (auto htWrap = mStart.ContainerAsHyperTextWrap()) {
length = htWrap->LengthForRange(
mStart.mOffset, mEnd.ContainerAsHyperTextWrap(), mEnd.mOffset);
}
return length;
}
NSValue* GeckoTextMarkerRange::Bounds() const {
nsIntRect rect;
if (mStart.mContainer->IsRemote() && mEnd.mContainer->IsRemote()) {
DocAccessibleParent* ipcDoc = mStart.mContainer->AsRemote()->Document();
Unused << ipcDoc->GetPlatformExtension()->SendBoundsForRange(
mStart.mContainer->AsRemote()->ID(), mStart.mOffset,
mEnd.mContainer->AsRemote()->ID(), mEnd.mOffset, &rect);
} else if (auto htWrap = mStart.ContainerAsHyperTextWrap()) {
rect = htWrap->BoundsForRange(
mStart.mOffset, mEnd.ContainerAsHyperTextWrap(), mEnd.mOffset);
}
NSScreen* mainView = [[NSScreen screens] objectAtIndex:0];
CGFloat scaleFactor = nsCocoaUtils::GetBackingScaleFactor(mainView);
NSRect r =
NSMakeRect(static_cast<CGFloat>(rect.x) / scaleFactor,
[mainView frame].size.height -
static_cast<CGFloat>(rect.y + rect.height) / scaleFactor,
static_cast<CGFloat>(rect.width) / scaleFactor,
static_cast<CGFloat>(rect.height) / scaleFactor);
return [NSValue valueWithRect:r];
}
void GeckoTextMarkerRange::Select() const {
if (mStart.mContainer->IsRemote() && mEnd.mContainer->IsRemote()) {
DocAccessibleParent* ipcDoc = mStart.mContainer->AsRemote()->Document();
Unused << ipcDoc->GetPlatformExtension()->SendSelectRange(
mStart.mContainer->AsRemote()->ID(), mStart.mOffset,
mEnd.mContainer->AsRemote()->ID(), mEnd.mOffset);
} else if (RefPtr<HyperTextAccessibleWrap> htWrap =
mStart.ContainerAsHyperTextWrap()) {
RefPtr<HyperTextAccessibleWrap> end = mEnd.ContainerAsHyperTextWrap();
htWrap->SelectRange(mStart.mOffset, end, mEnd.mOffset);
}
}
bool GeckoTextMarkerRange::Crop(Accessible* aContainer) {
GeckoTextMarker containerStart(aContainer, 0);
GeckoTextMarker containerEnd(aContainer, CharacterCount(aContainer));
if (mEnd < containerStart || containerEnd < mStart) {
// The range ends before the container, or starts after it.
return false;
}
if (mStart < containerStart) {
// If range start is before container start, adjust range start to
// start of container.
mStart = containerStart;
}
if (containerEnd < mEnd) {
// If range end is after container end, adjust range end to end of
// container.
mEnd = containerEnd;
}
return true;
}
}
}